U.S. patent number 8,323,122 [Application Number 13/192,394] was granted by the patent office on 2012-12-04 for method of making golf clubs.
This patent grant is currently assigned to Cobra Golf Incorporated. Invention is credited to Karl Clausen, Peter L. Soracco.
United States Patent |
8,323,122 |
Soracco , et al. |
December 4, 2012 |
Method of making golf clubs
Abstract
A method for making golf club heads includes using direct metal
laser sintering (DMLS), selective laser melting (SLM) and other
computer controlled high energy sintering or melting techniques to
form club heads with customized user parameters. The powdered
metals can be selected by type and quantity to achieve a desired
density or weight distribution. Club heads made by these techniques
are characterized by having customized parameters chosen for
individual golfers. By sintering powdered metal to form areas of
different porosity, club heads with desired weight distributions
can be achieved.
Inventors: |
Soracco; Peter L. (Carlsbad,
CA), Clausen; Karl (Carlsbad, CA) |
Assignee: |
Cobra Golf Incorporated
(Carlsbad, CA)
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Family
ID: |
42352523 |
Appl.
No.: |
13/192,394 |
Filed: |
July 27, 2011 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20110277313 A1 |
Nov 17, 2011 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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12468129 |
May 19, 2009 |
8007373 |
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Current U.S.
Class: |
473/349 |
Current CPC
Class: |
B33Y
10/00 (20141201); B22F 10/20 (20210101); B33Y
80/00 (20141201); A63B 60/02 (20151001); A63B
53/047 (20130101); A63B 53/04 (20130101); A63B
60/00 (20151001); A63B 53/0487 (20130101); A63B
53/0437 (20200801); Y10T 29/49 (20150115); B33Y
70/00 (20141201); B22F 2207/17 (20130101); A63B
2209/00 (20130101); A63B 53/0466 (20130101); Y02P
10/25 (20151101) |
Current International
Class: |
A63B
53/04 (20060101) |
Field of
Search: |
;473/324-350 |
References Cited
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Other References
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.
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|
Primary Examiner: Hunter; Alvin
Attorney, Agent or Firm: Leonardo; Mark S. Brown Rudnick
LLP
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser.
No. 12/468,129, filed May 19, 2009 and incorporated in its entirety
by reference herein.
Claims
What is claimed is:
1. A method of making a portion of a golf club head for playing
golf comprising: providing a powdered metal material comprising a
metal; and forming a metal portion of the golf club head layer by
layer from the powdered metal material by depositing the powdered
metal material on a substrate layer by layer and leaving at least
one void where no material is placed on the substrate with the
result that the metal portion has at least one void space formed
therein.
2. A method of making a portion of a golf club head for playing
golf comprising: providing a powered metal material comprising a
metal; and forming a metal portion of the golf club head layer by
layer from the powered metal material, wherein a first portion of
the metal portion has a first density and a second portion of the
metal portion as a second density different from the first density
and further wherein the metal portion of the golf club head is
formed having at least one void space therein.
3. A method of making a portion of a golf club head for playing
golf comprising: providing a powered metal material comprising a
metal; and forming a metal portion of a golf club head layer by
layer from the powdered metal material, Wherein a first portion of
the metal portion has a first density and a second portion of the
metal portion has a second density different from the first density
and further wherein a region of a topline, a heel, and an upper toe
portion of the golf club head is formed of the metal.
4. A method of making a portion of a golf club head for playing
golf comprising: providing a powdered metal material comprising a
metal; and forming a metal portion of the golf club head layer by
layer from the powdered metal material, wherein a first portion of
the metal portion has a first porosity, a second portion of the
metal portion has a second porosity, and the first porosity is
different from the second porosity and further wherein the first
portion comprises at least 95% of a total volume of the golf club
head.
5. A method of making a portion of a golf club head for playing
golf comprising: providing a powdered metal material comprising a
metal; and forming a metal portion of the golf club head layer by
layer from the powdered metal material, wherein a first portion of
the metal portion has a first porosity, a second portion of the
metal portion has a second porosity, and the first porosity is
different from the second porosity and further wherein the powdered
metal material comprises particles with an average diameter of less
than about 40 microns.
6. A method of making a portion of a golf club head for playing
golf comprising: providing a powdered metal material comprising a
metal; and forming a metal portion of the golf club head layer by
layer from the powdered metal material, wherein a first portion of
a metal portion has a first porosity, a second portion of the metal
portion has a second porosity, and the first porosity is different
from the second porosity and further wherein the metal portion
comprises at least on internal channel.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to methods of making golf club heads,
and more specifically, to a method of making iron type golf club
heads using powdered metal rather than conventional metal forgings
or castings.
2. Description of the Related Art
Golf clubs are formed through a variety of methods. Commonly, a
golf club head is forged or cast and then machined or ground and
polished to the requisite dimensions and desired aesthetic quality.
These processes have proven to be time consuming and
inefficient.
In addition, golf clubs are typically manufactured to fit an
average person of average dimensions. Thus, the same club is
manufactured regardless of the particular golfer's needs. This
standard approach to golf club manufacturing is utilized due to the
expensive and time consuming process associated with altering or
manufacturing a new mold to incorporate changes in club design.
Therefore, in order to save time and money, manufacturers use the
same mold that is not readily adjustable with respect to the
particular characteristics of the golf club. However, this presents
a problem due to the fact that not all golfers are built the same,
and not all golfers have identical swings. In addition, due to
manufacturing tolerances, many golf clubs that claim to be a
particular lie, loft, or face angle may be off by as much as
1.degree.. Due to the variety of golf swings, golfers, and
manufacturing flaws and/or tolerances, each individual golfer may
benefit from an optimization of lie angle, loft angle, or other
club head design parameter.
The lie angle of any golf club is the angle formed between the
center of the shaft and the ground line of the club when the club
is soled in its proper playing position (address position).
Therefore, a taller golfer is likely to benefit from an increase in
lie angle, which would allow for the golfer to comfortably address
the ball properly. In a similar fashion, a short golfer would
probably benefit from a reduction in lie angle.
Loft angle is a measurement, in degrees, of the angle at which the
face of the club lies relative to a perfectly vertical face. Using
a club with a high loft angle will typically result in a golf shot
with a high initial trajectory. In contrast, utilizing a club with
a low loft angle will typically result in a golf shot with a low
initial trajectory.
Currently, manufacturers rely on post-manufacturing methods for
custom fitting golf clubs, the majority of which involve placing
the club in a vice and bending the metal until the desired
specifications are met. However, frequent modifications or improper
bends may result in fatigue of the metal or weakening of the club
head.
Finally, due to manufacturing tolerances, current methods of
manufacturing frequently require additional steps to bring the club
close to the desired specifications. For example, a club head that
is designed to have a loft angle of 9.degree. may be manufactured
with a loft angle of 8.degree.. Therefore, the additional step of
bending the hosel is necessary to achieve the desired loft
angle.
As such, there remains a need in the art for a method of
manufacturing golf clubs that allows implementation of design
variations while maintaining efficiency and cost effectiveness. In
addition, there remains a need for a method of manufacturing golf
clubs that allows a designer to create a golf club near
specifications thereby reducing the need for finishing or bench
work.
SUMMARY OF THE INVENTION
The present invention relates to a method of making a golf club
head by applying a controlled source of energy to a powdered metal
to form a golf club head. The method includes selecting a club
design, selecting at least one design parameter, providing a
powdered metal, and applying a controlled source of energy to the
powdered metal to form a golf club head having a desired design
parameter.
The controlled source of energy may include a direct metal laser
sintering (DMLS) system, a selective laser melting system, an
electron beam melting apparatus, or similar apparatus.
The club design may be selected from a parametric CAD file and then
altered according to the designer's specifications. Alternatively,
the club design may be selected from a library of CAD files.
The designer may select from a wide range of parameters to
customize a golf club head. For example, the designer may select
any of the following parameters: weight, weight distribution,
bounce angle, lie angle, offset, loft angle, shape, hardness, sole
camber, sole width, cavity undercut, center of gravity, face
height, hosel outer diameter, hosel inner diameter, hosel taper,
hosel depth, toe height, groove width, groove depth, and groove
shape.
According to another aspect of the invention, the powdered metal
may be used alone or in combination with another powdered metal.
Powdered metals suitable for use in the invention include, but are
not limited to steel, stainless steel, iron, copper, bronze,
aluminum, tungsten, titanium, titanium alloy, chromium-cobalt
alloy, and combinations thereof.
In one embodiment, a first powdered metal may be used for a first
portion of the club head, and a second powdered metal may be used
for a second portion of the club head. The first powdered metal may
have a density that is greater than the density of the second
powdered metal. For example, the first density may be greater than
the second density by about 5 g/cm.sup.3. In addition, the first
density may be greater than about 10 g/cm.sup.3. Alternatively, the
first density may be greater than about 7 g/cm.sup.3.
In one embodiment, the density is controlled by controlling the
porosity of portions of the club head. For example, a first portion
may be made of a sintered metal having a first porosity, and a
second portion may be made of a sintered metal having a second
porosity. The porosity of the first portion may be greater than the
porosity of the second portion, which results in a lower density
for the first portion.
The low density first portion may occupy about 1% to about 99% of
the entire volume of the club head. Alternatively, at least 95% of
the total volume of the golf club head is formed from the low
density first portion. The porosity of the low density first
portion may be about 99% porosity to about 1% porosity. In another
embodiment, the low density first portion has a porosity that is
greater than about 90%.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features and advantages of the invention can be ascertained
from the following detailed description that is provided in
connection with the drawings described below:
FIG. 1 is a front view of an iron type club head of the present
invention;
FIG. 2 is a rear view of a cross section of a club head of the
present invention;
FIG. 3 is a rear view of a club head of the present invention;
FIG. 4 is a cross sectional view of a club head of the present
invention taken along 1-1 of FIG. 3;
FIG. 5 is a cross sectional view of a club head of the present
invention taken along 1-1 of FIG. 3;
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is directed to a process for manufacturing
golf clubs using an additive process. For example, powdered metal
sintering and metal deposition are suitable processes for use in
the present invention. The process may be used to manufacture any
type of golf club head including, but not limited to: irons, woods,
putters, utility clubs, and wedges.
Powdered metal sintering systems involve a bed of metal powder that
is sintered or melted layer by layer by a laser or electron beam to
create metal parts. After the part has been created, the
surrounding powder can be brushed away or shaken out of the part.
In addition, a variety of metal powders can be melted in these
systems. There are a number of commercially available systems
suitable for use in the present invention. For example, the "MCP
Realizer", a selective laser melting system, which is the product
of Mining and Chemical Products Limited of Germany, can create
parts from any number of metals including the following powders:
zinc, bronze, stainless steel, titanium, chromium-cobalt, silicon
carbine, and aluminum oxide. In addition, various machines from EOS
of Germany are available that rely on direct metal laser sintering
(DMLS). ARCAM of Sweden produces machines that rely on electron
beam melting (EBM) technology.
Direct Metal Laser Sintering (DMLS) has recently emerged outside
the golf industry as a way of manufacturing metal parts. The DMLS
process involves using a laser that fires into a layer of powdered
metal guided by a computer program. DMLS is an "additive"
technology that sinters very fine powders layer by layer from the
bottom up until the product is completed. The process begins by the
input of 3-D CAD files and, a control program converts the CAD
files into instructions for controlling the layer by layer
formation of the metal parts. The layer by layer formation is
accomplished by laser sintering a `first layer` of approximately 20
to 40 micron powder onto a steel platform. The platform then lowers
by approximately 20 to 80 microns, a fresh layer of powder is swept
over the previously sintered layer, and the next layer is sintered
or added on top of the previously built one. The additive process
is repeated until the desired part is complete.
Metal deposition systems use a 3D printing process to create metal
parts in a similar manner to how ink is deposited from print heads
on an inkjet printer. Multiple heads can be incorporated into these
systems to increase the production speed. Metal deposition systems
are currently available from FCDBIC AB of Sweden and ProMetal, LLC
of Troy, Mich. This process may be used to create a solid part with
uniform or non-uniform material properties or to add layers of
powdered metal to an existing substrate. For example, a metal
deposition device may be employed to coat a portion of a surface of
a golf club head with a material that has a high density in order
to alter the center of gravity or other design specification of the
golf club head.
The general procedure that applies to all machines is to design a
part in a 3-D CAD application, convert the CAD file to an STL file,
and then transfer the STL file to the machine for processing. "STL"
stands for stereolithography; and is a file format that is widely
used to describe the shape of a three dimensional object. This file
format is supported by many software packages and is widely used
for transferring CAD models to rapid prototyping and direct
manufacturing machines.
There are several advantages to powdered metal sintering
production. For example, batch size and batch configuration, or
mixing different quantities of each part depending on the demand
for each part, is easily adjustable without significantly affecting
part cost. This is a direct result of the ability of the process to
rapidly implement production of a new part by merely altering a CAD
file or selecting a new CAD file. This is in contrast to parts
created from tools for which it is necessary to accurately forecast
the quantities of each part so that the appropriate number of tools
will be made.
In addition, design time can be reduced by creating functional
prototypes directly from the CAD model. Eliminating the need for
prototype tooling can reduce the time before prototype designs can
be tested for performance, durability and appearance. The
development and production time can be shortened for a design by
eliminating or reducing the need for other manufacturing processes.
For example, DMLS is more efficient than the casting process,
because DMLS eliminates the time for creating tools, wax
preparation, creating ceramic shells, pouring metal into shells,
breaking shells, cutting parts off of casting trees, and grinding
off parting lines and weld beads. Further, the process is capable
of implementing changes in design without the need to alter or
manufacture a new tool or mold. For example, a change in the design
of a club head manufactured by a casting process requires the
precise modification of the mold or the production of an entirely
new mold. This is a time consuming and expensive process. By
contrast, the powdered metal sintering process merely requires the
changes to be made to a CAD file, and the process will manufacture
the club head based on the CAD file. Therefore, changes can be
easily implemented by the designer without the need for a halt in
production or the construction of new tools or molds.
DMLS and similar machines have further advantages over casting and
forging in that DMLS can produce more consistent parts. Current
manufacturing methods such as casting result in variation in part
weight and size due to manufacturing tolerances and changes in
environmental conditions, such as heat and humidity. Due to these
inconsistencies, parts are intentionally created with extra size
and weight so that they can be ground down to the proper
specifications. Parts created on a DMLS machine can be created with
more consistent size and weight. Since there is less hand finishing
required, parts can be created closer to the net finish size, and
fewer adjustments need to be made to account for the manufacturing
processes. Part size can be adjusted to match the design model by
properly calibrating the DMLS machine. In addition, since powdered
metal sintering is an additive process, there is a significant
reduction in waste resulting from material that must be cut away
after molding or forging.
It is also possible to use the DMLS process to create tooling for
conventional processes such as casting, forging, stamping, and
injection molding. This tooling can be created directly from the
CAD data and does not require programming that is needed for
machined tools.
In addition, an additive process such as DMLS can create undercuts
or internal channels in tools which would be impossible or
difficult to do with a CNC machine. Undercuts and other features
may require the use of a support structure, which may be made using
an additive process or other known methods. Upon formation of the
undercut, the support is removed by a known method. For example,
the support may be formed from a polymer material and subsequently
heated to remove.
Materials
Suitable materials for use in the process are powdered metals
composed of particles with an average diameter of less than about
40 microns. Preferably the average diameter is less than about 25
microns. Alternatively, the average diameter may be less than about
35 microns. The average diameter may be between about 30 and about
40 microns. The powdered metal can be any powdered metal available
on the market capable of being sintered and includes, but is not
limited to, 303 stainless steel, 304 stainless steel, 431 stainless
steel, 432 stainless steel, iron, copper, bronze, aluminum,
tungsten, chromium-cobalt alloy, titanium and titanium alloys, or
similar materials and combinations thereof. The materials may also
be combined with another material in order to vary the composition
of portions of the club head to achieve a desired characteristic
for a particular portion. For example, 303 stainless steel may be
used for the body portions of the club head including the top line,
heel, toe, and sole portions of the club and a titanium alloy may
be used to produce the face portion of the club head.
Powdered Metal Sintering
The process includes selecting a set of design parameters to match
specifications of a specific golfer, providing a powdered metal,
and applying energy to the powdered metal to form the club head. In
one embodiment a powdered metal sintering process, such as DMLS, is
used to form a club head. Initially, the designer inputs a design
from a CAD file. However, the system may include a library of
existing CAD files or a parametric CAD file that can be modified by
inputting a set of new design parameters. The parametric CAD files
include a basic shape of the club head, and the designer selects
from a list of parameters to customize the club accordingly. The
parameters may include, but are not limited to: density, weight
distribution, bounce angle, lie angle, offset, loft angle,
hardness, sole camber, sole width, cavity undercut, center of
gravity, face height, hosel outer diameter, hosel inner
diameter/taper, hosel depth, toe height, groove width, groove
depth, and groove shape, or combinations thereof.
Referring to FIG. 1, a club head 10 of the present invention has a
typical iron type club head shape that includes hosel 12, sole 15,
heel 14, and toe 16. A ball striking face 18 has a plurality of
parallel, horizontally disposed grooves formed in the surface of
the face 18. A lie angle 20 is defined by the center line (CL) of
hosel 12 and the horizontal plane (OP) on which the club rests when
addressing the ball. The lie angle, in conventional club
manufacturing processes, is set when the clubs are forged or cast,
and in general, the factory set lie angle is suitable for some
golfers, but not all. In forged and cast clubs, the hosel must be
bent relative to the remainder of the club head to change the lie
angle to suit a particular golfer. In the present invention, the
lie angle is one of the parameters that can be customized for each
club head of each set to suit the specifications of an individual
golfer. Similarly, the bounce angle is defined by the horizontal
plane and the line of the sole of the club head next to the club
face. This angle can also be adjusted by custom fitting steps, in
the prior art, after forging or casting. In the present invention,
the bounce angle is another parameter that can be customized for an
individual golfer without subsequent processing steps, such as
bending, grinding or otherwise working the metal which comprises
the club head.
A particularly useful aspect of the powdered metal sintering
process is the ability to control the density of various portions
of the club head. Varying the density of certain portions of the
club head allows the designer to distribute mass throughout the
club head in order to control characteristics of the club head such
as the center of gravity and moment of inertia. Density control may
be accomplished in a variety of ways.
In one embodiment, the process uses at least two different powdered
metals or alloys to form the club head. Regions of higher and lower
density material, or regions of different materials, can be used to
change the center of gravity of the club head, or otherwise
redistribute weight in a manner intended to improve playability of
the clubs.
Referring to FIG. 2, a region of low density material 26 is formed
in the topline, heel, and upper toe portions of the club head, and
a region of high density material 28 is formed in the lower portion
of the club head, thereby achieving a lower center of gravity.
Although, FIG. 2 only shows one orientation of density
distribution, the high and low density portions may be distributed
in a variety of ways to achieve a desired specification. For
example, a material with a high density may be used in one or more
"heavy" portions, and a material with a low density may be used in
one or more "light" portions. The heavy portions may be formed from
a material with a density greater than about 1 g/cm.sup.3.
According to one aspect of the invention, the heavy portions may be
formed from a material with a density greater than about 3
g/cm.sup.3. In one embodiment, the heavy portions may be formed
from a material with a density greater than about 7 g/cm.sup.3. In
one embodiment, the heavy portions are formed from a material with
a density greater than about 10 g/cm.sup.3, In another embodiment,
the heavy portion is composed of a material with a density that is
greater than about 15 g/cm.sup.3, In addition, the heavy portion
may have a density that is greater than the light portion(s) by at
least about 1 g/cm.sup.3. In another embodiment, the heavy portion
has a density that is greater than the light portion by about 3
g/cm.sup.3. The heavy portion has a density that is greater than
the light portion by about 5 g/cm.sup.3. Alternatively, the
material of the heavy portion may have a density that is greater
than the material of the light portion by about 10 g/cm.sup.3.
In another embodiment, the density of various portions of the club
head is controlled by varying the porosity of the sintered metal.
Porosity is a measure of the void spaces in a material, and is
measured as a fraction, between 0-1, or as a percentage between
0%-100%. For example, by controlling the amount of powder, it is
possible to control the density, in terms of porosity, of the
particular powdered metal used in the process, Typically, when a
metal part is manufactured, it is expected that the finished
product has approximately 0% porosity, with limited inclusions.
By using the formation methods of the present invention, it is
possible to change the porosity of the material, layer by layer,
area by area, to achieve a desired density. This is accomplished by
varying the amount of powdered metal used for certain areas of the
club head. A reduction in the amount of powder used for a
particular layer results in a layer with a greater porosity and a
lower density.
Referring to FIG. 3, a club head 10 has a hosel 12, a heel 14 and
toe 16. A sole 15 extends between the heel 14 and toe 16. The rear
surface 48 is shaped to have a centrally located low density
portion 46 surrounded by a higher density portion 48. In effect,
club head 10 behaves similar to a cavity-back type club because the
orientation of low density portion 46 allows for mass to be freed
up and distributed towards the perimeter of the club head. This
orientation leads to an increase in the moment of inertia (MOI) of
the club head. Inertia is a property of matter by which a body
remains at rest or in uniform motion unless acted upon by some
external force. MOI is a measure of the resistance of a body to
angular acceleration about a given axis, and is equal to the sum of
the products of each element of mass in the body and the square of
the element's distance from the axis. Thus, as the distance from
the axis increases, the MOI increases, making the club more
forgiving for off-center hits. In addition, moving or rearranging
mass to the club head perimeter enlarges the sweet spot and
produces a more forgiving club.
For example, the porosity and the density may be altered using a
DMLS process. The process may be programmed to space lines of
material placed on a substrate to form a layer. The program may
allow for a wide space between the lines, which results in a layer
formed from less powder. This process forms a layer with a high
percentage of porosity and low density. By contrast, a layer may be
formed wherein the DMLS process is programmed to place little or no
space between the lines. The lack of space between the lines
results in a layer that is formed with a low porosity and a high
density. FIG. 5 shows an example of the interior of a club head
where spaces (66) and lines of material (68) form the interior of a
club head.
Another method of increasing porosity is to program the process to
leave pockets or voids where no material is placed on the
substrate. FIG. 4 shows the interior of a club head where voids 56
contain no material.
In one embodiment, voids or spaces are formed by programming a
process as outlined above. The voids may be interconnected
throughout the club head. Next, one or more of the voids or spaces
are filled with a light weight polymer or other low density
material. Alternatively, the interior of the club head may comprise
a skeleton or frame made with a high porosity. A low density
material may then be injected to fill the areas in and around the
frame. The low density material may have a density that is less
than about 1.3 g/cm.sup.3.
In one embodiment, a first amount of material may be used for the
formation of layers for a first portion of the golf club head, and
a second amount of material may be used for the formation of layers
for a second portion of the golf club head. The first amount of
material is less than the second amount of material, which results
in a club head with a first portion that is more porous than the
second portion. Therefore, the density of the first portion is less
than the density of the second portion. This allows for a lighter
overall structure, freeing up weight to optimize play
characteristics of the golf club.
In one embodiment, the first portion may comprise about 1% to about
99% of the entire volume of the club head. The first portion may
comprise about 5% to about 95% of the entire volume of the club
head. In another embodiment the first portion may comprise at least
about 95% of the total club head volume. In another embodiment, the
first portion of the club head may comprise greater than about 85%
of the total volume of the club head.
For example, the first portion may comprise the interior of the
club head and the second portion may comprise only the surface of a
portion of the club head. In one embodiment the surface of the club
head is less than about 0.050 in. thick. Alternatively, the surface
of the club head is less than 0.040 in. thick. In another
embodiment, the surface is about 0.030 in. thick.
In addition, the porosity of the first portion may range from about
99% porosity to about 1% porosity. In one embodiment, the porosity
of the first portion ranges from about 95% to about 5%.
Alternatively, the porosity of the first portion may be greater
than 90%. The porosity of the first portion may range from about
20% to about 80%. In another embodiment, a third portion may be
formed that has a porosity that is greater than the first porosity,
which results in a greater density for the first portion in
comparison to the third portion.
In another embodiment, a hollow club head may be created using the
powdered metal sintering process in combination with a conventional
method. Portions of the club head may be made according to the
process described above, and subsequently the portions are joined
by a welding process. For example, a front portion may include the
face and the sole, and a back portion may be welded to the front
portion in a manner that creates a hollow area between the front
and back portion.
Metal Deposition
Another aspect of the present invention is to utilize a metal
deposition process to coat a substrate with powdered metal. For
example, an existing part or club head may be inserted into the
metal deposition apparatus, to apply a coating material to be part
of the club head. This process may be used to apply a protective
layer over parts of the club that come into contact with objects.
For example, the sole of the club may be coated with a material
that is harder than other parts of the club in order to prevent
damage from repeated impacts with the ground.
In one embodiment, the designer uses the metal deposition process
to coat selected portions to achieve a desired club attribute such
as center of gravity, moment of inertia, hardness, or other club
characteristic. For example, a high-density material may be
deposited onto the heel portion of the club in order to move the
center of gravity toward the heel of the club.
By contrast, a low density substrate may be coated with a powdered
metal. The substrate may be a polymer or non-metallic in nature.
For example, a low density polymer can be coated with a powdered
metal to form a club head. As a result, the club head is made
lighter and mass can be added to desired locations to achieve
various specifications such as moment of inertia, center of
gravity, hardness, or other characteristic.
In one embodiment, a portion of a substrate may be coated with a
metallic coating by utilizing a vapor deposition or chemical
deposition process in combination with a metal deposition
process.
In addition, the modification techniques described for the powdered
metal sintering process are also applicable in the metal deposition
process. Specifically, the density, hardness, and weight
distribution can be modified by utilizing powdered metals of
different densities and/or varying the porosity of the sintered
metal.
Notwithstanding that the numerical ranges and parameters setting
forth the broad scope of the invention are approximations, the
numerical values set forth in the specific examples are reported as
precisely as possible. Any numerical value, however, inherently
contain certain errors necessarily resulting from the standard
deviation found in their respective testing measurements.
Furthermore, when numerical ranges of varying scope are set forth
herein, it is contemplated that any combination of these values
inclusive of the recited values may be used.
The invention described and claimed herein is not to be limited in
scope by the specific embodiments herein disclosed, since these
embodiments are intended as illustrations of several aspects of the
invention. Any equivalent embodiments are intended to be within the
scope of this invention. Indeed, various modifications of the
invention in addition to those shown and described herein will
become apparent to those skilled in the art from the foregoing
description. Such modifications are also intended to fall within
the scope of the appended claims. All patents and patent
applications cited in the foregoing text are expressly incorporated
herein by reference in their entirety.
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